TASCAM PORTA 02mk2 KNOB OR SLIDER PLUS A MYSTERY

I had a moment to list some Porta 2 stuff that had been sitting on my desk

All is as it should be but in the bag was another two slider switch caps they are identical to the Porta 2 one but different colours , I bought these in a lot from a service centre but I have no idea where they come from if any one has any ideas let me know please